This invention relates to forward gliding ram-air inflated canopy parachutes of the type disclosed in U.S. Pat. No. 3,724,789 to Snyder, and more particularly to a load distributing system for the canopy of such parachutes.
Ram air inflated parachutes of the foregoing type have an airfoil-shaped canopy, the foward glide and load carrying characteristics of which depend on the maintenance of a relatively high lift/drag ratio which is adversely affected by distortion of the outer canopy surfaces from the ideal airfoil curvatures and by the drag of the load lines through which the payload is suspended from the canopy. From experience, a canopy of a given size has been provided with an optimum number of load lines attached to the canopy at chordwise spaced load points designed to establish inflated canopy surfaces with acceptable distortion from the ideal airfoil lift curvature. Although less distortion from the ideal airfoil surface occurs with the use of more load lines, the drag is also increased so that some compromise is necessary.
It has also been found advisable to locate the chordwise spaced load point attachments of the load lines to the bottom surface of the canopy along the ribs which internally separate the canopy inflating air cells. Such air cells extend chordwise from the open intake at the leading edge of the canopy to the trailing edge. Thus, distortion from the ideal airfoil surface will occur along those ribs at which the load points are located. To minimize the number of load lines utilized and the drag associated therewith, heretofore some of the rib locations on the bottom canopy surface are free of load point attachments. In this manner, a predetermined lift/drag ratio is achieved for the desired forward glide characteristic of any given size canopy and associated payload capacity.
It is therefore an important object of the present invention to provide a ram-air inflated, forward glide parachute having an unexpectedly large payload capacity.
Another object in accordance the foregoing object is to provide the ram air inflated parachute with an improved airfoil lift surface so as to maintain forward glide characteristics for larger payloads.
Yet another object of the invention is to provide a ram air inflated parachute with more than what was heretofore believed to be an optimum number of load lines in order to more reliably suspend heavier payloads.